Young adult women have had the greatest increase in prevalence of metabolic syndrome (MetS) over time, and prevalence is highest in Hispanic women, compared with women of other ethnicities. Factors contributing to the high prevalence of MetS in Hispanic women are unknown. This study was conducted to determine if physical activity or fitness were associated with individual features of MetS in young Mexican and Mexican-American women, and if the associations were independent of fat mass. Sixty young Mexican and Mexican-American women participated in the study. MetS was defined according to the Adult Treatment Panel III. A fasting blood sample was drawn for the measurement of glucose, insulin, high-density lipoprotein cholesterol (HDL-c), and triglycerides. Physical activity was assessed by questionnaire and accelerometer. Fitness was assessed by progressive treadmill test to exhaustion and ventilatory threshold. Body composition was assessed with Bod Pod. Multivariate regression was used to establish the independent contributions of physical activity and fitness to the individual features of MetS. After controlling for fat mass and fat-free mass, physical activity was found to be independently related to HDL-c and fitness was found to be independently related to triglycerides (p < 0.05). The independent associations between physical activity, fitness, and features of MetS were mediated by, rather than independent of, fat mass. Fat mass was independently related to triglycerides, systolic blood pressure, and diastolic blood pressure. Although physical activity and fitness were related to features of MetS, these associations were not independent of fat mass.

Little is known about effects of acculturation on disease risk in young Mexican and Mexican-American women living in a border community. The purpose of this study was to examine relationships between acculturation and features of metabolic syndrome (MetS) in Mexican and Mexican-American women (n = 60) living in the largest US-Mexico border community. Acculturation was measured by the short acculturation scale for Hispanics and birthplace. Body composition was measured by Bod Pod and daily physical activity was measured by questionnaire and accelerometer. Increased acculturation was related to individual features of MetS and increased risk of MetS. These relationships were mediated by fat mass rather than inactivity. Fat mass mediates the relationships between acculturation and individual features of MetS in young Mexican and Mexican-American women. These findings suggest that fat mass, rather than inactivity, is an important contributor to disease risk in young Mexican and Mexican-American women living in a large US/Mexico border community.

Despite the benefits associated with regular physical activity, there is little epidemiological evidence to support positive health outcomes when meeting physical activity guidelines in high-risk ethnic groups, such as Hispanic women. We compared cardiovascular disease risk factors between young Hispanic women who meet and those who do not meet current physical activity guidelines. Height, weight, waist circumference, and blood pressure were measured in 60 Hispanic women aged 20-39 years. Lipids, C-reactive protein, insulin, and glucose were assessed. Body composition and cardiovascular fitness were assessed by BodPod and maximal oxygen uptake (VO₂(max)) respectively. Participants wore an accelerometer and average minutes (assessed in 10-min bouts) spent in light, moderate, and hard daily activity for weekdays and weekends was determined. Seventy percent of participants did not meet the recommended physical activity guidelines, whereas 30% did so. Following current physical activity guidelines was associated with significantly lower mean cholesterol (mean ± s: 4.2 ± 0.8 vs. 4.7 ± 0.9 mmol · l⁻¹) and triglycerides (0.7 ± 0.3 vs. 1.1 ± 0.6 mmol · l⁻¹), and higher fat-free mass (43.3 ± 3.8 vs. 40.2 ± 5.1 kg) and relative (40.4 ± 7.6 vs. 35.6 ± 7.0 ml · kg⁻¹ · min⁻¹) and absolute (2.5 ± 0.3 vs. 2.1 ± 0.4 litres · min⁻¹) VO₂(max) (P < 0.05). These findings suggest an improved health status in women who meet versus those who did not meet current physical activity guidelines.

OBJECTIVETo investigate the associations of markers of insulin resistance with cardiovascular disease risk factors and inflammation in young, normal-weight, Hispanic women.RESEARCH DESIGN AND METHODSSeventy-one normal-weight (BMI <25 kg/m2) Hispanic women (age, 20–39 years) participated in a fasting blood draw for glucose, insulin, lipids, and inflammatory markers; a glucose tolerance test; anthropometric and blood pressure measurements; body composition by dual-energy x-ray absorptiometry; and measurements of cardiorespiratory fitness via Vo2max and daily physical activity by accelerometer.RESULTSSix percent of participants had impaired fasting glucose, 14% had impaired glucose tolerance, and 48% had at least one cardiovascular disease risk factor. Homeostasis model assessment of insulin resistance (HOMA-IR) and fasting insulin were positively correlated with glucose, triglycerides, systolic blood pressure, and diastolic blood pressure, and were negatively correlated with adiponectin (P < 0.05). The 2-h insulin was positively correlated with diastolic blood pressure, triglycerides, and high-sensitivity C-reactive protein. HOMA-IR and fasting insulin remained significantly and positively related to glucose, triglycerides, and blood pressure after adjustment for body composition. The relationships between markers of insulin resistance and adiponectin and high-sensitivity C-reactive protein were attenuated after adjustment for body composition.CONCLUSIONSSurrogate markers of insulin resistance were associated with cardiovascular disease risk factors and inflammation in young, normal-weight, Hispanic women. Our findings suggest that HOMA-IR, fasting, and 2-h insulin may be important clinical markers for identifying young, normal-weight, Hispanic women who may be at risk for development of type 2 diabetes and cardiovascular disease. Our findings show the importance of early screening for prevention of type 2 diabetes and cardiovascular disease in this population.

The purpose of this study was to assess cardiac function and arteriovenous oxygen difference (a-vO(2) difference) at rest and during exercise in young, normal-weight (n = 20), and obese (n = 12) men and women who were matched for age and fitness level. Participants were assessed for body composition, peak oxygen consumption (VO(2peak)), and cardiac variables (thoracic bioimpedance)-cardiac index (CI), cardiac output (Q), stroke volume (SV), heart rate (HR), and ejection fraction (EF)-at rest and during cycling exercise at 65% of VO(2peak). Differences between groups were assessed with multivariate ANOVA and mixed-model ANOVA with repeated measures controlling for sex. Absolute VO(2peak) and VO(2peak) relative to fat-free mass (FFM) were similar between normal-weight and obese groups (Mean ± SEE 2.7 ± 0.2 vs. 3.3 ± 0.3 l min(-1), p = 0.084 and 52.4 ± 1.5 vs. 50.9 ± 2.3 ml kg FFM(-1) min(-1), p = 0.583, respectively). In the obese group, resting Q and SV were higher (6.7 ± 0.4 vs. 4.9 ± 0.1 l min(-1), p < 0.001 and 86.8 ± 4.3 vs. 65.8 ± 1.9 ml min(-1), p < 0.001, respectively) and EF lower (56.4 ± 2.2 vs. 65.5 ± 2.2%, p = 0.003, respectively) when compared with the normal-weight group. During submaximal exercise, the obese group demonstrated higher mean CI (8.8 ± 0.3 vs. 7.7 ± 0.2 l min(-1) m(-2), p = 0.007, respectively), Q (19.2 ± 0.9 vs. 13.1 ± 0.3 l min(-1), p < 0.001, respectively), and SV (123.0 ± 5.6 vs. 88.9 ± 4.1 ml min(-1), p < 0.001, respectively) and a lower a-vO(2) difference (10.4 ± 1.0 vs. 14.0 ± 0.7 ml l00 ml(-1), p = 0.002, respectively) compared with controls. Our study suggests that the ability to extract oxygen during exercise may be impaired in obese individuals.